Pantograph-trolley.



I. E. CASE. PANTOGRAPH TROLLEY. APYLIGATION FILED 13110.11, 1907.

1,075,331. Patented Oct. 14, 1913.

2 SHEET SSHEET 1.

WITNESEEEI INVENTEIR. WGP J FRANK Eli/x5e- ATT Y.

F. E. CASE.

PANTOGRAPH TROLLEY. APPLICATION FILED DEO.11, 1907.

Patented'Oct. 14, 1913.

2 SHEETS-SHEET 2.

WITNEEIEIEEI |NVENTEIR FRANK E- CA5: E.

/ bY ATTY pairs s raws PATENT oration.

FRANK n. (men, or

sc'Hniv'Ec'rAnY, NEW YORK, ASSIGNOR To GENERAL ELECTRIC COMPANY, A CORPORATION or new Yon mannerisms-reenter.

Specification of Letters Patent.

Patented allot. ME, 1913.

Application filed December 11, 1907. semi No. eoaoss.

.inen't of trolley, as is necessarily the case when said springs are carried on the lower ends of the upper arms or members of the trolley. I

Another object of the invention is to utilize air pressure to raise the trolley, and also to unlock and release it when it is to belowered.

In carrying out the invention, I arrange the springs in a horizontal position so that in the operation of raising and operating the trolley their mass cannot affect the latter. They are connected with the lower ends of the upper members of the trolley by connecting rods. The springs are also attached to cross-heads which are connected to piston rods,- whose istons are located in opposite ends of-a horizontal cylinder substantially in the plane of the springs. \Vhen fluid pressure is admitted to t is cylinder between the two pistons, the latter are forced apart and the springs are put under tension. The pull of the springs is communicated to the members of the trolley by the connecting rods, so that the trolley is raised. When the contact arrives at the proper height, a toggle locks the pistons in this position and the fluid pressure can be released from the cylinder. In order to trip the toggle and allow the trolley to drop, fluid pressure is admitted to a device responsive to fluid pressure, such as a small cylinder whose piston rod is arranged to kick open the toggle.

In the accompanying drawings, Figure 1 is a side elevation of a pantograph trolley embodying my invention and shown in its raised position; Fig. 2 is a top plan view of the same, partly broken away; Fig. 3 is a side elevation showing the trolley lowered;

structure. Each pair of arms is connected by a shaft 6 7, to which are secured, respectively, the upper arms or members 8 9, which are pivotally connected to the transverse contact device or shoe 10. The shafts 1 2 carry rock arms 11 which are connected by equalizing rods 12, whereby the two shafts are obliged to rock in unison through equal angles in opposite directions, as the trolley is raised or lowered.

Secured on the shafts (3 7 are the rock arms 13 let which are connected respectively by the rods 15 16 with rock arms 17 18 loosely mounted on the shafts 1 2. To these latter rock arms are attached one end of the springs 19 20, which are located preferably in substantially the same horizontal plane between the two shafts 1 2. The other ends of the springs 19 are attached to a cross head 21 located near the shaft 2, while the ends. of the spring 20 are connected with a cross-head 22 lying near the shaft 1. Provision is made for adjusting the tension of each of the springs by means of a screwthreaded rod 23 to which the spring is secured, said rod passing through the end of the cross-head and being provided with nuts 24.

The cross-heads are connected respectively with two piston rods 25 26 whose pistons 27 28 occupy opposite ends of a main cylinder 29 arranged horizontally between the two shafts 1 2, and substantially in the plane of the springs. A pipe 30 is connected with the middle of the cylinder and serves to convey thereto a charge of fluid pressure, preferably compressed air coming from suitable source of supply, such as the reservoir of the air brake system. Steam or other motive fluid may be substituted for air, if desired.

A lug i-ll'projectsup from each cross-head to a point above the cylinder 29. A bar 32 is attachedto each lug and slides to and fro in a guide 33 erected on the cylinder.

The neighboring ends of these bars are contoward the cylinder, asshown in Fig. 1. In. this position, the links form a toggle which has straightened and passed the center, so that it resists any effort of the pistons'to move back into the cylinder. To break the to gle, there is placed under its joint a li ter 35,. preferably a loop encircling the cylinder. The lifter is connected to the piston rod 36. of a movable abutment, such as the piston 37 located ina small upright cylinder 38 underneath the main cylinder. The space below this piston is in communication with a source of fluid pressure, preferably by means of a pipe 39.

The operation of the device is as follows: Assume the trolley to be lowered, as shown in Fig. 3, with the pistons 27 28 at or near the middle of the main cylinder and the springs not under tension. To raise the trolley, air is admitted through the pipe 30, forcing the main pistons apart and causing the cross-heads to exert a pull on the springs. This in turn is communicated through the loose rock arms 17 18 to the connecting rods 15 16 and by them trans mitted to the rock arms 13 14 on the shafts 6 7. The rocking of these shafts lifts the arms or upper members 8 9 carrying the trolley shoe, so that the parts quickly assume the position shown in Fig. 1. After the air has exhausted from the main cylinder, the tension of the springs is borne by the bars 32 and links 34, which keep the cross-heads separated. Any downward pressure on the trolley shoe is resisted yieldingly by the springs, through the connecting rods and the loose rock arms. When it is desired to lower the trolley, air is admitted through the pipe 39 into the small lifter cylinder and the piston 37 is forced upward, causing the lifter to kick ofi the toggle and let the tension of the springs move the main pistons back into the cylinder 29. It will be seen that this construction relieves the trolley arms 4 and 5 0f the weight of the springs; relaxes the springs when they. are not in service and the trolley is lowered; and uses the air pressure only when the .trolley is to be raised or lowered, but without requiring the expenditure of any energy while the trolley" is in service or out of service.

What I claim as new and desire to secure by Letters Patent of the United States, is,

1. A pantograph trolley comprising movable upper and lower members and horizontally disposed springs, means for sup horizontal springs connected at one end with said arms.

3. A pantograph trolley comprising movable members and springs, a cylinder, pistons therein connected with said springs, means for locking said pistons when said springs have been put under tension, and means for simultaneously releasing said pistons.

4. A pantograph trolley comprising movable members and lifting springs, a cylinder, pistons therein connected with said lifting springs, and links pivotally connected to said pistons and adapted tohold them apart when said springs have been put under tension.

5. A pantogroph trolley comprising mov able members and lifting springs, a cylinder, pistons therein connected with said lifting springs, means for locking both of said pistons when said springs have been put under tension, and means for simultaneously releasing said pistons in order to lower said trolley.

6. A pantograph trolley comprising movable members and lifting springs, a cylinder, pistons therein connected with said springs, a toggle for locking said pistons when the springs have been put under tension,and means responsive to fluid pressure for breaking said toggle in order to lower said trolley.

7. A pantograph trolley comprising movable members and lifting springs, a cylinder, pistons therein carrying cross-heads connected with said springs pivoted links con- FRANK E. CASE.

Witnesses;

BENJAMIN B. Horn,

Orronn. 

